If you are turning your crankshaft clockwise (you should because that is the way the engine rotates) you will find that 10 deg before TDC comes before TDC.
If you rotated the engine counter clockwise, then the timing might be off by the slack in the timing chain.
So I would recommend that you pull the dist cap, turn the engine clockwise using the crankshaft balancer bolt, and have someone look at the rotor as you do. When it is getting close to #1, then stop before TDC. Don't pass it and back up because that plays with the slack in the chain.
With the crank stopped at 10 deg before TDC, verify that rotor is indeed pointing at the #1 tower, and that the points and prongs are lined up exactly.
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If that is set right, and please do check it, then try electrically unplugging the MAP sensor and see if it runs much better. If so look for a broken vacuum tube. There is a tap on the upper plenum that one side runs to the MAP sensor, and the other side runs to the fuel pressure regulator. If either vacuum line is cracked and not giving full manifold vacuum to the MAP sensor, the ECM will be running the engine quite rich. You can also a test run a rubber vacuum hose directly from that nipple on the upper intake to the MAP sensor. The Fuel Pressure Regulator's reading of the intake manifold pressure is not as critical as the MAP sensors. The MAP sensor is the #1 sensor that the ECM uses to determine how much fuel to inject. Since your engine is running so crappy, your problem has to be one of the bigger things, not a smaller thing like the intake air temp sensor.
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Also when the RPMs drop, what does the tach do? Does it operate normally (show the actual RPMs even when the engine is dying?) or does it the tach seem to drop out with the engine? Was the replacement dist new or used? Used dist, and tach totally dying with the engine dropping out could be weak magnets in the dist rotor. But then most likely you would have huge problems getting it to start also.
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No scanner cable eh?
[This message has been edited by phonedawgz (edited 07-27-2013).]